{"product_id":"uckasayfy-dual-battery-isolator-12v-140a-vsr-lead-acid-only-ip65-sealed-automatic-battery-management","title":"UCkasayfy Dual Battery Isolator 12V 140A VSR — Lead‑Acid Only, IP65 Sealed Automatic Battery Management","description":"\u003cp\u003e\u003cstrong\u003eUCkasayfy Dual Battery Isolator 12V 140Amp is a voltage-sensitive relay that automatically combines and separates your vehicle’s starter and auxiliary batteries to keep the primary battery charged while protecting it from drains.\u003c\/strong\u003e\u003c\/p\u003e\n\n\u003cp\u003eThis compact VSR is engineered for 12V lead-acid systems and provides automatic, hands-free battery management for UTVs, boats, RVs, trucks, trailers, ATVs and campers. It closes at around 13.3 volts to allow charging both batteries in parallel and opens near 12.8 volts to stop auxiliary loads from discharging the starter battery. Designed with an IP65-rated, silicone-sealed housing, the relay tolerates wet and dusty conditions but is not suitable for lithium battery chemistries.\u003c\/p\u003e\n\n\u003ch3\u003eHow does this VSR preserve my main starter battery?\u003c\/h3\u003e\n\n\u003cp\u003eThe isolator monitors charging voltage and only connects batteries when the alternator or charger raises system voltage above its cut-in threshold, preventing accessory loads from draining the starter battery when the engine is off. It also disconnects at a lower threshold so the starter battery retains enough reserve to start the vehicle.\u003c\/p\u003e\n\n\u003cul\u003e\n  \u003cli\u003eAutomatic cut-in at ~13.3V and cut-out at ~12.8V\u003c\/li\u003e\n  \u003cli\u003ePrevents deep discharge of the primary battery\u003c\/li\u003e\n  \u003cli\u003eSimple, maintenance-free operation — no manual switching\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eWill this isolator work in harsh outdoor or marine conditions?\u003c\/h3\u003e\n\n\u003cp\u003eYes — the device is built with a silicone-sealed interior and an IP65-rated enclosure to resist water spray and dust, making it suitable for exposed installations on boats, ATVs and utility vehicles. The sealed construction also increases reliability in dusty or vibration-prone environments.\u003c\/p\u003e\n\n\u003cul\u003e\n  \u003cli\u003eSilicone-sealed internals for environmental protection\u003c\/li\u003e\n  \u003cli\u003eIP65 rating for dust and water spray resistance\u003c\/li\u003e\n  \u003cli\u003eCompact footprint fits tight engine bays and battery compartments\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eCan the isolator charge the main battery from the auxiliary battery in emergencies?\u003c\/h3\u003e\n\n\u003cp\u003eYes — the relay supports reverse charging: if the primary battery is depleted and the auxiliary has charge, closing the circuit lets the auxiliary supply the main battery. Ensure any accessories connected to the secondary battery are properly fused and that wiring runs are within recommended lengths.\u003c\/p\u003e\n\n\u003cul\u003e\n  \u003cli\u003ePermits reverse charging from auxiliary to main when necessary\u003c\/li\u003e\n  \u003cli\u003eRecommend fusing accessories within 0.98 ft for safety\u003c\/li\u003e\n  \u003cli\u003eDesigned for lead-acid systems; do not use with lithium batteries\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eHow do I know it fits my vehicle and installation needs?\u003c\/h3\u003e\n\n\u003cp\u003eThe isolator is rated for continuous loads up to 140 amps, compact enough for cramped spaces, and compatible with most 12V lead-acid systems found in cars, RVs, trailers, and marine craft. It’s an easy addition to existing wiring harnesses or new dual-battery setups when you need automatic parallel charging without added complexity.\u003c\/p\u003e\n\n\u003cul\u003e\n  \u003cli\u003e140A rating suits alternators on many recreational and utility vehicles\u003c\/li\u003e\n  \u003cli\u003eSmall size for flexible mounting locations\u003c\/li\u003e\n  \u003cli\u003eWorks with conventional lead-acid, AGM and flooded batteries (not lithium)\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003cp\u003eWho is this for: Adventurers, fleet operators and DIY mechanics who run accessories from a secondary battery and want a reliable, automatic way to keep their starter battery charged. It’s ideal for boaters, campers, off-road riders and tow-vehicle owners who need a low-maintenance relay with good environmental protection. Avoid this model if your system uses lithium batteries — choose a lithium-compatible management device instead.\u003c\/p\u003e\n\u003csection class=\"product-faq-snippet\"\u003e\u003ch3\u003eFAQ\u003c\/h3\u003e\n\u003cdiv class=\"faq-item\"\u003e\n\u003cp class=\"faq-q\"\u003eQ: Is this isolator compatible with lithium batteries?\u003c\/p\u003e\n\u003cp class=\"faq-a\"\u003eA: No. The UCkasayfy 12V 140A isolator is not suitable for lithium battery chemistries.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"faq-item\"\u003e\n\u003cp class=\"faq-q\"\u003eQ: What voltages does the relay cut in and out at?\u003c\/p\u003e\n\u003cp class=\"faq-a\"\u003eA: It typically cuts in at about 13.3V and cuts out near 12.8V to protect the starter battery.\u003c\/p\u003e\n\u003c\/div\u003e\u003c\/section\u003e","brand":"UCkasayfy","offers":[{"title":"Default Title","offer_id":48085543026846,"sku":"B093T2T1CP","price":34.98,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0781\/2041\/9486\/files\/uckasayfy-front-view-relay.jpg?v=1785872338","url":"https:\/\/northtrailauto.ca\/products\/uckasayfy-dual-battery-isolator-12v-140a-vsr-lead-acid-only-ip65-sealed-automatic-battery-management","provider":"North Trail Auto","version":"1.0","type":"link"}